On the applicability of Postʼs lattice

For decision problems $\Pi (B)$ defined over Boolean circuits using gates from a restricted set B only, we have $\Pi (B){?}_m^{{\mathrm{AC}}^0}\Pi (B^{\prime })$ for all finite sets B and $B^{\prime }$ of gates such that all gates from B can be computed by circuits over gates from $B^{\prime }$. In this note, we show that a weaker version of this statement holds for decision problems defined over Boolean formulae, namely that $\Pi (B){?}_m^{{\mathrm{NC}}^2}\Pi (B^{\prime }\cup \{\wedge ,\vee \})$ and $\Pi (B){?}_m^{{\mathrm{NC}}^2}\Pi (B^{\prime }\cup \{0,1\})$ for all finite sets B and $B^{\prime }$ of Boolean functions such that all $f\in B$ can be defined in $B^{\prime }$.     

Critical evaluation and thermodynamic optimization of the V–O system

The V–O system has been critically evaluated and thermodynamically assessed based on the available phase diagram and thermodynamic data using the CALPHAD method. The liquid phase over the whole composition range from metallic liquid to oxide melt is described by the modified quasichemical model with five species: V^II, V^III, V^IV, V^V and O, which takes short-range ordering in liquid solution into account. All solid solutions are modeled considering respective crystal structures. A set of self-consistent thermodynamic parameters of the V–O system is obtained and the available experimental data are reproduced well within experimental error limits. Especially for the VO_x solid solution, the site fractions of vacancies in both vanadium and oxygen sublattices are reproduced well using the present model and parameters.     

British Museum’s smart idea

The British Museum in London has adopted smart card technology to assist service delivery and enhance the visitor experience. As part of its Compass project, the museum is using a smart card purse and print management system to store, print and pay for print-outs and photocopies on 50 Compass workstations, which give access to 5000 on-line artefacts.This is a short news story only. Visit www.compseconline.com for the latest computer security news.     

An algebraic axiomatization of the Ewald’s intuitionistic tense logic

Ewald (J Symbolic Logic 51(1):166–179, 1986) considered tense operators \(G\) , \(H\) , \(F\) and \(P\) on intuitionistic propositional calculus and constructed an intuitionistic tense logic system called IKt. The aim of this paper is to give an algebraic axiomatization of the IKt system. We will also show that the algebraic axiomatization given by Chajda (Cent Eur J Math 9(5):1185–1191, 2011) of the tense operators \(P\) and \(F\) in intuitionistic logic is not in accordance with the Halmos definition of existential quantifiers. In this paper, we will study the IKt variety of IKt-algebras. First, we will introduce some examples and we will prove some properties. Next, we will prove that the IKt system has IKt-algebras as algebraic counterpart. We will also describe a discrete duality for IKt-algebras bearing in mind the results indicated by Or?owska and Rewitzky (Fundam Inform 81(1–3):275–295, 2007) for Heyting algebras. We will also get a general construction of tense operators on a complete Heyting algebra, which is a power lattice via the so-called Heyting frame. Finally, we will introduce the notion of tense deductive system which allowed us both to determine the congruence lattice in an IKt-algebra and to characterize simple and subdirectly irreducible algebras of the IKt variety.     

An improved firefly algorithm for numerical optimization problems and it’s application in constrained optimization

Engineering with Computers - Metaheuristic algorithms are successful methods of optimization. The firefly algorithm is one of the known metaheuristic algorithms used in a variety of applications....     

Design of robotic arm’s action to imitate the mechanism of an animal’s consciousness

We are attempting to develop a system so that a user is able to let robots perform an intellectual action that has a healing and friendly feeling. Based on the development process of the actions and consciousness of animals, we constructed a structure model which connects consciousness and action hierarchically, built a valuation function for action selection, and developed software to control the action of a robot. This software is called Consciousness-Based Architecture (CBA). With it, our aim is to connect a user and robot as closely as possible and to allow smooth communications between them by developing an emotional system that takes notice of consciousness. In our system, the robotic arm’s finger is outfitted with a small Web camera, which allows the arm to recognize external information so that the robot can select various actions that comply with certain factors in the outside environment. Furthermore, by using the actuator of the robotic arm, the system we have built provides a correspondence between the robot’s internal states, such as the degree of rotation angle, and the outside temperature. In the present study, a motivation model which considers the outside environment and the internal states has been built into the CBA, and the behavior of the robotic arm has been verified.     

Control and trajectory optimization of an aircraft’s alignment with the desired track

The synthesis of the control with the optimal trajectory length is constructed for the problem of aligning an aircraft with the desired track with the ground speed vector direction along the desired track. The solution is based on the maximum principle and involves the use of numerical methods for solving the boundary value problem and analytical investigations for determining the set of possible extremals and comparing the lengths of the trajectories when selecting the optimal one. As a result of these investigations, the switching and separation lines are determined that bound the regions in the phase space which correspond to different values of the optimal relay control.     

A “poor man’s” approach to topology optimization of natural convection problems

Structural and Multidisciplinary Optimization - Topology optimization of natural convection problems is computationally expensive, due to the large number of degrees of freedom (DOFs) in the model...     

From ‘simulation optimization’ to ‘simulation configuration’ of systems

Simulation optimization aims at determining the best values of input parameters, given an output criterion. We address here the much more complex case where design options have to be chosen, which can themselves necessitate choices about other sub-options, as well as numerical parameters. This so-called configuration problem is addressed using simulation associated with a distributed evolutionary algorithm, and is illustrated through an example. This approach allows a large variety of new types of problems to be solved, such as design of complex dynamic systems. In the light of these results, the limits in the optimized configuration of systems are shown to be now determined by the modeling and simulation tools and concepts. In this respect, a possible research direction, based on so-called functional simulation, is discussed and some research perspectives are introduced.     

Introduction to the Geometer’s Angle

Geometer Rachel Fletcher introduces the Geometer’s Angle, a column in the Nexus Network Journal dedicated to geometrical constructions, the procedures for drawing them, their use, significance and symbolism.     

An analysis of a firm’s capacity in Mazda’s Keiretsu

Capacity is defined as the power resulting from the specific position of a company in a network organization. This article extends the theory of network organizations to examine Mazda’s Yokokai Keiretsu, and proposes a new approach to calculating a firm’s capacity in a network. Capacity is divided into two categories, take-in capacity and take-out capacity, and the gap between them is called the capacity difference. We analyze the impact of capacity difference as a determinant of corporate performance in network organizations, thus providing a new perspective for successful corporate management.     

An observer’s information dynamics: Acquisition of information and the origin of the cognitive dynamics

Conventional information science considers an information process, but traditionally uses the probability measure for random states and Shannon’s entropy as the uncertainty function of these states.This paper presents a new approach, based on an integral information measure of the random process.An entropy functional (EF) on the trajectories of the process accumulates and encodes the process’ inner connections between the information states.The application of a variation principle (VP) to the EF determines the process’ information path functional (IPF), whose extremal trajectories describe the informational dynamics of this process.Information dynamics with the VP invariant relations evaluate the information content of a random process, expose its information code and reveal a conserved (hidden) information, produced at an acquisition of the process information.By introducing both objective and subjective information observers, we consider the observers information cognitive dynamics and neurodynamics, based on the EF–IPF approach.The universal nature of information process’ dynamics and regularities, discovered in the information observers, have many applications not only in cognitive and intelligent systems, but also in different biological, social and economic systems.     

Modeling of a ship’s entry into water using the boundary element method

The mathematical model and algorithm of a numerical analysis of the dynamic entry of a body falling into incompressible fluid is considered. The boundary element method is used. The ways of reducing computational costs for the repeated solution of a boundary value problem for many instants on the basis of coordinate transformations are presented.     

An approach to determining Shor’s dual quadratic estimates

For a general quadratic problem, an analog is formulated as a homogeneous quadratic problem. The estimates ψ* constructed based on Shor’s dual quadratic estimates for these problems are proved to be equal. It is shown that, for the case of a homogeneous quadratic problem, finding ψ* is reduced to an unconstraint minimization problem for a convex function. The study was partially sponsored by the grant UKM2-2812-KV-06 (CRDF Cooperative Grants Program). __________ Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 89–99, March–April 2008.     

Improving the effect of fuzzy clustering on RBF network’s performance in terms of particle swarm optimization

This paper proposes a novel training algorithm for radial basis function neural networks based on fuzzy clustering and particle swarm optimization. So far, fuzzy clustering has proven to be a very efficient tool in designing such kind of networks. The motivation of the current work is to quantify the exact effect of fuzzy cluster analysis on the network’s performance and use it in order to substantially improve this performance. There are two key theoretical findings resulting from the present work. First, it is analytically proved that when the standard fuzzy c-means algorithm is used to generate the input space fuzzy partition, the main effect this partition imposes to the network’s square error (i.e. performance index) can be written down in terms of a distortion function that measures the ability of the partition to recreate the original data. Second, using the aforementioned distortion function, an upper bound of the network’s square error can be constructed. Then, the particle swarm optimization (PSO) is put in place to minimize the above upper bound and determine the network’s parameters. To further improve the accuracy, the basis function widths and the connection weights are fine-tuned by employing a steepest descent approach. The main experimental findings are: (a) the implementation of the PSO obtains a significant reduction of the square error while exhibiting a smooth dynamic behavior, (b) although the steepest descent further decreases the error it finally obtains smaller reduction rates, meaning that the strongest impact on the error reduction is provided by the PSO, and (c) the improved performance of the proposed network is demonstrated through an extensive comparison with other related methods using a 10-fold cross-validation analysis.     

A comparative analysis of the EU GDPR to the US’s breach notifications

One component of the newly implemented European Union General Data Protection Regulation (GDPR), a revision of a 1995 directive, is mandatory breach notification. The US has no such federal law. This means companies must satisfy multiple US laws and that makes it more challenging to comply. This study is a comparison of the GDPR with the statutes of the 50 US states, highlights the challenges companies face and reveals the types of decisions companies must make to be in compliance with these statutes.